Fluorite
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Mineral NameFluorite
Chemical FormulaCaF₂
Mohs Hardness4
Crystal Systemcubic
Lustervitreous
Streak Colorwhite
Cleavageperfect octahedral (four directions)
Fractureconchoidal to uneven
Specific Gravity3.18
Colorspurple, green, blue, yellow, colorless
Transparencytransparent to translucent
Type LocalityWidespread, notable localities include Illinois (USA), Weardale (England), Naica (Mexico), Huanggang (China)
Mineral GroupHalides
Usesflux in steelmaking, hydrofluoric acid production, optical lenses, jewelry, collector specimens
Associated Mineralsquartz, calcite, barite, galena, sphalerite, pyrite
Raritycommon
Description
This specimen displays intergrown cubic or octahedral crystals of fluorite, exhibiting distinct purple and green color zoning, set within a brownish, possibly iron-stained, matrix.
Geological Context
Fluorite commonly forms in hydrothermal veins, often associated with metallic ore deposits, and can also be found in granites, pegmatites, and some sedimentary rocks.
